Makoto Isshiki is a high school student who befriends Yuuta Togashi on their first day of class due to mutual loneliness. He possesses light to dark skin, short dark brown hair—eventually shaved into a crew cut—and indigo eyes. His standard attire is the school uniform: a long black jacket with white accents, red and white tie, black pants, and brown shoes.

Driven by a persistent fixation on female classmates, Makoto crafts profiles and rankings of girls to gain their notice, inviting repeated warnings and comedic blunders. A pivotal shift occurs when Kumin Tsuyuri pats his head, sparking authentic romantic feelings that eclipse his superficial pursuits, revealing his capacity for sincere attachment.

During junior high, Makoto sported an unpopular baseball crew cut that accentuated his childish appearance. His family history includes hereditary baldness, with his father losing hair at thirty-five; Makoto anticipates similar loss before twenty. This insecurity intensifies after punishment for creating a "cutest girl" poll, leading him to impose a self-penalty: shaving his head entirely, reviving his association with the crew cut.

Throughout the series, Makoto initially joins the Light Music Club to mingle with girls, wielding a red electric guitar he plays poorly. He later departs amid senior resistance to engage with the main friend group, transitioning from comic relief to a supportive ally. He notably encourages Yuuta to confess his feelings to Rikka, validating their bond. His participation in group endeavors, especially alongside Kumin, underscores his deepening social integration.

In subsequent seasons, Makoto's presence lessens, featuring sporadically for humor. Movies, OVAs, and spin-offs introduce no further backstory or developments beyond his television arc.